Locked Out of Global Admin – Lost Authenticator – Case 2602060010000939 – Need Escalation

if you do not have an Azure Support Plan or other support contract this is how it goes.

you can only open a SR through Azure Support and insist it is routing to Entra / Identity Team.
Prio cannot raised without support plan. if you had one you need to give them the data like tenant ID, subscription ID with that support plan. Depending on the plan you can request escalation to B or A.

For the future consider a break glass account 

https://blog.merill.net/p/service-principal-as-a-plan-b-emergency

https://learn.microsoft.com/en-us/entra/identity/role-based-access-control/security-emergency-access